Intent is the buzz word that let her slide on lack of Professional Responsibility and Common Sense.

Bingo!!

Her "intent" in the use of a private server rather than the professionally responsible use of the department server is left open to question. And her answer is even more questionable. At best, it is, as you say, professionally irresponsible. At worst, it has the strong appearance of avoiding transparency, of hiding intentions which she would rather not be known.